This blog will list news about all aspects of scorpion biology and important taxonomical updates from The scorpion Files. The Scorpion Files is a leading information source about scorpions, and has among others an updated list of all extant families, genera and species.(C) Jan Ove Rein and The Scorpion Files.

22 June, 2017

Carlos E. Santibáñez-López and co-workers have recently published an article on the phylogeny of diplocentrid scorpions. I have to be honest and say that this stuff is very much over my head and I just have to ask you to check out the abstract and the article for more details. Unfortunately, phylogeny and molecular taxonomy was not on the curriculum when I got my zoology educations in the previous millenium.

In a revision of the higher scorpion systematics, Soleglad & Fet (2003) abolished the family Diplocentridae and included
all genera into Scorpionidae. This have been criticized by parts of the scorpion expert community, who treat this taxa as a valid family (Diplocentridae). This is also the case with the present article. The scorpion Files still lists Diplocentridae as a subfamily, but this
is under consideration and may change in the time to come after I get input from my contacts in the scorpion expert community.

Abstract:Morphology still plays a key role in the systematics and phylogenetics of most of the scorpion families and genera, including the Diplocentridae Karsch, 1880. The monophyly of this family, and the monophyly of its two subfamilies is supported by morphological characters; however, neither hypothesis has been tested using molecular data. The lack of a molecular phylogeny has prevented the study of the evolution of morphology within the family. Here, we examine the morphological evolution of several key character systems in diplocentrid systematics. We tested the monophyly of the Diplocentridae, and subsequently the validity of its two subfamilies using a five-locus phylogeny.We examined the variation and evolution of the shape of the carapace, the external surface of the pedipalp patella and the retrolateral surface of the pedipalp chelae of males and females. We also examined the phylogenetic signal of discrete and continuous characters previously reported. We show that Diplocentridae is monophyletic, but Nebinae is nested within Diplocentrinae. Therefore, Nebinae is synonymised with Diplocentrinae (new synonymy). Finally, we show that a new character system proposed here, tarsal spiniform and macrosetal counts, retains high phylogenetic signal and circumscribes independently evolving substructures within this character system.

21 June, 2017

Matthew Graham and co-workers have recently published an article on the phylogeography of Smeringurus vachoni (Stahnke, 1961) (Vaejovidae) from the USA. One of the main conclusions is that Smeringurus vachoni does not comprise of two subspecies (S. v. vachoni and S. v. immanis), but instead consists of at least 11 mitochondrial clades. The authors synonymize S. v. vachoni andS. v. immanis under the single species S. vachoni, but they encourage future taxonomic investigations using more rigorous species delimitation approaches. I refer to the abstract and the article for further details.

Abstract:Recent syntheses of phylogeographical data from terrestrial animals in the Mojave and Sonoran deserts have revealed a complex history of geologic and climatic vicariance events. We studied the phylogeography of Smeringurus vachoni to see how vicariance events may have impacted a large, endemic rock scorpion. Additionally, we used the phylogeographical data to examine the validity of two subspecies of S. vachoni that were described using unconventional morphological characters. Phylogenetic, network and SAMOVA analyses indicate that S. vachoni consists of 11 clades mostly endemic to isolated desert mountain ranges. Molecular clock estimates suggest that clades diversified between the Miocene and early Pleistocene. Species distribution models predict a contraction of suitable habitat during the last glacial maximum. Landscape interpolations and Migrate-n analyses highlight areas of gene flow across the Colorado River. Smeringurus vachoni does not comprise two subspecies. Instead, the species represents at least 11 mitochondrial clades that probably diversified by vicariance associated with Pleistocene climate changes and formation of ancient lakes along the Colorado River corridor. Gene flow appears to have occurred from west to east across the Colorado River during periodic river avulsions.Reference:
Graham MR, Wood DA, Henault JA, Valois ZJ, Cushing PE. Ancient lakes, Pleistocene climates and river avulsions structure the phylogeography of a large but little-known rock scorpion from the Mojave and Sonoran deserts. Biological Journal of the Linnean Society. 2017;Ahead of Print:1-14. [Subscription required for full text]

15 June, 2017

Kang & Brooks have recently published an epidemiological study on scorpion envenomations in the USA between 2005 and 2015.

Abstract:Introduction: Previous studies of scorpion envenomation in the United States (US) have focused on Arizona and the bark scorpion, Centruroides sculpturatus. Although many other scorpion species live in the US, information about envenomations in other states is lacking.Methods: Nationwide scorpion exposures from 2005 to 2015 were analyzed using the National Poison Data System.Results: Of the 185,402 total exposures, Arizona (68.2%), Texas (10.3%), and Nevada (4.2%) were the top contributors. However, six other southern states reported greater than 100 cases annually, primarily during the warmer months and evening hours. Envenomations occurred most often in a home (97.8%) and were typically managed on-site (90.1%). Pain was the most common effect nationwide (88.7%). Arizona had the highest frequencies of sensory, neuromuscular, and respiratory effects along with higher hospitalization and ICU admission rates, although the latter appeared to drop over the study period. In contrast, local skin effects such as erythema and edema were more common outside of Arizona. Children under 10 years of age in Arizona and Nevada had the highest rates of systemic effects, hospitalization, and ICU admission.Conclusions: Scorpion envenomations occurred throughout the southern US with similar seasonal and daily variations. Common clinical effects included pain, local edema, and erythema, except in Arizona and Nevada where severe systemic symptoms were more common. Systemic effects correlated with high rates of ICU admissions and intubations, especially in children under 10 years of age. Reference:Kang AM, Brooks DE. Nationwide Scorpion Exposures Reported to US Poison Control Centers from 2005 to 2015. J Med Toxicol. 2017;13(2):158-65. [Subscription required for full text]

13 June, 2017

Kari McWest and co-workers recently published an article on the scorpion fauna of the Central and Southern High Plains and associated breaks and canyonlands of northwestern Texas. The six species in the region are described and new records information about habitats are presented.

The articles has an identification key for the species in the region.

Abstract:The scorpion fauna of the Central and Southern High Plains and associated breaks and canyonlands of northwestern Texas includes six species: Centruroides vittatus (Say, 1821), Chihuahuanus coahuilae (Williams, 1968), Ch. russelli (Williams, 1971), Maaykuyak waueri (Gertsch & Soleglad, 1972), Paruroctonus pecos Sissom & Francke, 1981, and Paruroctonus utahensis (Williams, 1968), Paruroctonus pecos Sissom & Francke, 1981 is recorded in northwestern Texas for the first time. Numerous new records and a key for identification are provided for all six nominal species recorded within the study area. Ecological and natural history notes are also presented, and species records are projected with GIS mapping.

09 June, 2017

Frantisek Kovarik and co-workers have recently published an article where they present an investigation of the holotype of Microananteroides mariachiarae Rossi & Lourenço,
2015 (Buthidae). The authors conclude that this taxa is a junior synonym of Akentrobuthus atakora
Vignoli & Prendini, 2008 (Buthidae).Abstract:The African monotypic scorpion genus Microananteroides Rossi et Lourenço, 2015 and its single species M. mariachiarae Rossi et Lourenço, 2015, from Ghana, are herein demonstrated to be junior synonyms, respectively, of Akentrobuthus Lamoral, 1976 and A. atakora Vignoli et Prendini, 2008 from neighboring Benin. We provide detailed high-resolution color photographs of the holotype of M. mariachiarae and further show its real trichobothrial pattern, which was incorrectly depicted in the original description.

06 June, 2017

Wilson Lourenco has recently described a new species of Opisthacanthus Petters, 1861 (Hormuridae) from the border areas between Suriname and Brazil.

Opisthacanthus surinamensis Lourenco, 2017

The biogeography of the species of Opisthacanthus in the area is discussed.

Abstract:A re-analysis of the geographical distribution of neotropical species of the genus Opisthacanthus Peters (Scorpiones: Hormuridae) is proposed. A new species, Opisthacanthus surinamensis sp. n., is described from the Region of the Serra do Tumucumaque in the border between Suriname and Brazil (Sipaliwini Savannah in Suriname). This is the first record of a species of the genus Opisthacanthus from Suriname and the third one from Brazil. The total number of species in the Neotropical region is now raised to 10, although some of the Venezuelan species may yet require confirmation. The known geographical distribution of the genus is also enlarged with a new location in the Guayana region (sensu MORI, 1991).